Shuttle for sewing-machines



ITNESSES: I J v mm (No Mdel.) l

' J. H. WAY. l SHUTTLE EUR SEWING MACHINES.

10.507,698. Patented oct. 31, ,1893.

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UNITED STATES PATENT OEEICE.

JOHN H. WAY, OF PHILADELPHIA, PENNSYLVANIA.

SHUTTLE FOR SEWING-MACHINES.

SPECIFICATION forming part of Letters Patent No. 507,698, dated October31, 1893.

Application tiled April 2.1, i890. Serial No. 348,851. (No model.)

To all whom it may concern: i

Be it known that I, JOHN H. WAY, of Philadelphia, in the State ofPennsylvania, have invented certain new and useful Improvements inOscillating Shuttles for Sewing-Machines, whereof the following is aspecification, reference being had to the accompanying drawings,wherein- Figure 1 represents a side view of a shuttle embodying myinvention, as seen looking toward the end or head of the sewing machine.Fig. 2 is a View of the opposite side of the shuttle from that shown inFig. l. Fig. 3 is an edge View of the shuttle, when opened so as toremove the bobbin. Fig. 4 is a central section through the shuttle,taken on the axis of the bobbin; and Figs. 5 and 6, are respectively topand side views of the spring washer, by means of which the bobbin isheld in place.

In the use of oscillating shuttles, as now commonly constructed, it isfound difficult to continue to sew, after a considerable portion of thethread h'as been unwound from the bobbin. Thus either a very largepercentage of the thread upon the bobbin is practically sacrificed, orelse such repeated adjustments of the tension are required as to greatlyincrease the labor of manufacture, and, consequently, enhance the costof the product. I have found that in some cases it is impossible toutilize more than one-half of the thread upon a bobbin, as after thatpoint the strain required to pull off the thread becomes so excessive asto disorganize the tension of the sewing machine. The primary cause ofthis difficulty lies in the fact that, in the usual method ofconstruction, the bobbin finds its bearings for rotation, not at itscenter, but near its circumference, the two sides of the shuttle beingformed with overlapping flanges around the seat, or opening of thebobbin, which lianges when closed, press more or less firmly against theedges of the bobbin. The

great amount of wear which the bobbins showV around their edges givesevidence of the extent of the friction caused in this manner. Thisfriction can be overcome when the bobbin is full and the leverageexerted by the thread in pulling off is` relatively great, but as thediameter of the thread coil is reduced, the leverage for the pull is ofcourse rapidly diminished,while the friction at the bearings remainsunchanged, until finally a point is reached where the thread pulls odwith so much difficulty that the bobbin has to be discarded and a fullone substituted. The object of my inventionis to overcome this difculty,and I accomplish it in the following manner:

Referring to the drawings, A represents what may be termed the main bodyot' the shuttle, constituting one side of the bobbin case, the otherside, D, forming the remainder of-such case, being hinged to the mainbody by the pivot, d.

B represents the horn or beak of the shuttle, which is formed in onepiece with the main body thereof, in the ordinary manner.

The diametric spring-piece, F, (which also constitutes the support forone of the bobbin journals) is secured at one end only, preferably bymeans of a screw, f, across the opening of the bobbin, and a toe, d,formed upon the pivoted end of the side, D, bears upon the free end ofsaid spring-piece, F, so as to normally tend to close the two sides ofthe shuttle together. The action of said spring is indicated in Fig. 3,where .the shuttle is represented as open. This feature, however,constitutes no portion of my invention, and is merely described by.reason of its reference to other parts.

The bobbin, C, is provided with a central opening, which lits looselyover the pin or stud, e, centrally mounted in the spring-piece, F, so asto afford a central bearing at that side of the bobbin. Across theopening in the opposite side, D, of the shuttle is a diametric bar, E,which is rigidly attached to, or formed in one piece with that side ofthe-shuttle, and said piece has at its central part a conebearing-piece, b, which extends into the opening of the bobbin and formsthe bearing 0n that side.

By reference to Figs. l and 2 it will be seen that there is a freespace, e, between the periphery of the bobbin and the opening in thecase, there being in this instance no flanges around said opening.

Intermediate between the spring-piece, F, and the proximate face of thebobbin, is an elastic washer, G, preferably of the shape shown in Figs.5 and 6, where it is represented as having four inwardly curvedspring-arms,

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adapted to bear upon the face of the bobbin. Said Washer slips over thepin, c, and tends to press the bobbin away from the side of the case andtoward the cone bearing-piece, b, but said cone bearing-piece does notpermit the proximate face of the bobbin to come in contact with thestrip or piece, E. It will thus be seen that the only frictional contactbetween the bobbin and the inclosing case of the shuttle occurs on theone side at the conical bearing-piece, b, and on the other sideimmediately around the periphery of the stud, c, since although the armsof the spring Washer, G, extend out toward the periphery, the onlybearing surface of the Washer upon the case or shuttle proper, occursaround the stud, c. The extent of this bearing surface should not besubstantially larger than the minimum diameter of the thread coiled uponthe bobbin itself, so that there is thus never any leverage against thepull of the thread, but throughout the Whole operation a very decidedleverage in its favor.

The usual tension device, t, having been properly adjusted for thethread, T, the bobbin, C, is inserted in its case, and the two inclosingsides, A and D, are shut together. The thread, T, is then insertedthrough the openings ot' the tension,t, and the operation ot' theshuttle takes placein the usual manner. I prefer to use the springWasher, G, in order to prevent the bobbin from over-running, orunwinding too freely, but the tension ot' said Washer may be very lightindeed, so as l to merely Overcome any such tendency and therefore neednot be considered as an element in the tension proper.

In the arrangement shown, the openings of the bobbin-case arerepresented as ot' the Same diameter all the Way through, or Wth- Outflanges around their inner edges, but, inasmuch as the bobbin is heldaway from both sides of the case, viz: on the one hand by the springWasher, G, and on the other by the wide flare of the conicalbearing-piece, b, such detail of construction is not absolutelyessential. The presence or absence of su :h flanges has no effect uponthe bobbin, where the latter is held clear of contact therewith.

While therefore I have indicated this as the preferred form of myinvention, I do not limit myself to the precise embodiment shown.

I claiml. The combination with the mainbody of the case and the stud cconnected therewith, of the part D attached to said main body andcarrying a conicalbearing piece b, thebobbin C, and the spring Garranged to press the bobbin against the cone, substantially asdescribed.

2. The combination with the main body of the case, the spring F attachedto one side thereof, and the stud c carried by said spring, of the partD pivoted to said main body and having a toe bearing against the freeend of spring F, and carrying a conical bearing piece b, the bobbin Cloosely fitting on stud c, and the springG also loosely fitting on thestud and having arms pressing the bobbin against the cone b,substantially as shown and described.

JAMES H. BELL, E. REEsE.

